hand scribbled numbers on the inner fender panel on the driver side

[kokovovoru]

Hi,
We recently bought a '12 X5 50. I have a few nub and stupid questions. Are the the fender panels of the LCI X5 made out of the same plastic as the pre-LCI X5. Just noticed it tonight as I "feeling" the car - please don't laugh at me. The other nub- might be serious - question is that when I look into the driver side (not passenger side as I previously wrote) of the engine bay, I noticed that there's an eight-digit, hand scribbled numbers written upside down on the inner fender wall. It seemed like it was written with fine point white pen, but when I tried to use my hand to wipe it off, I couldn't seem to wipe the numbers off. Why would they (dealership or BMW) "write", instead of stamping, numbers on the inner fender panel? Can someone chime in on this?